Why does she want to Breakup?

Okay, so my girlfriend who's been with me for 4 years, has decided to end things and asked for time cause everything that has happened in the relationship has hit her all now, we have had our rough patches but we talked and moved on, I met her today and she had tears in her eyes with how thing's have become between us, she let me hold her but she said she needs time to figure things out on what she wants, she was distant from me not telling me her whereabouts, not sharing things and I was begging for her time, but after today I'm confused as to how to take this forward, I also had the fear that she has found someone else and not telling me but she made it very clear that there is no one, what do you think I should do to get her back?

Why does she want to Breakup?
Post Opinion